(I found this on David Cox's site, as a chapter by chapter commentary or book for theWord. Great idea, but nearly impossible to use. So, I extracted the text, made the comments verse by verse, and made sure all the verse references were properly linked. I also bolded the beginning of each margin note and italicized the language indicator (Hebrews or Greek). Finally, I put the elements of each margin note on a separate line to make it readable.)

From the Compiler
These marginal notes are available in scans and published reprints of the 1611, but we believe that listing them all together and in modern spelling makes it much easier to study the notes in depth, or to do quick visual scans. The digital text of the notes allows for keyword searches, among other advantages.

Ways in which the marginal notes are valuable

Sometimes the notes shed light on an obscure passage

The meaning of the names of Bible characters revealed in the notes are often of interest

Also the meaning of some biblical terms (such as Bethel, meaning house of God)

It reveals that Bible translation work is not as simple and straightforward as some people imagine

It illustrates the absurdity of never deviating from translating in a literal fashion. The notes for a verse that illustrates this vividly is Gen_25:18, where "he did eat of his venison" in literal Hebrew would have been "venison was in is mouth" according to the marginal notes.

Why are the marginal notes left out of virtually all modern printings of the KJV? We present the following theories:

Extra material as in marginal notes costs more to print

Popularity of study Bibles that do not leave room for these marginal notes

Lack of demand, as the notes often deal with technicalities that do not concern the overwhelming majority of Bible readers

Misc. technical details of interest

The famous phrase "rock of ages" is not found in the text of the KJV, but rather in the margin at Isa_26:4.

The very last marginal note in the 1611 was a typo at Rev_20:13. For the word hell in the text, it had the marginal note "Or, hell."

There are no notes for the entire book of Philemon.

At least 9 entire verses were rewritten in marginal notes.

There are 6,565 marginal notes in the OT, and 777 in the NT, for a total of 7,342 marginal notes*

*Apochrypha not included. Scrivener's totals were 767 for the NT, 6,637 for the OT, for a total of 7,404 marginal notes. We used a spreadsheet program to help avoid human error in counting.

Heeding the warning of the KJV translators
Many of the marginal notes reveal thousands of instances in which the KJV translators were forced to interpret as part of their translation work. The KJV translators were not always certain that they had made the correct interpretation, and hence the marginal note. In the preface of the 1611 they explained that we should not dogmatize on the basis of their interpretation:

...it hath pleased God in his divine providence, here and there to scatter words and sentences of that difficulty and doubtfulness, not in doctrinal points that concern salvation, (for in such it hath been vouched that the Scriptures are plain) but in matters of less moment ... in such a case, doth not a margin do well to admonish the Reader to seek further, and not to conclude or dogmatize upon this or that peremptorily? ... They that are wise, had rather have their judments at libery in differences of readings, then to be captivated to one, when it may be the other.

Although we believe the KJV is trustworthy, we warn the reader that some in their zeal to defend the KJV go too far, and are guilty of what the KJV translators warned about.
The notes indicate a desire on the part of the KJV translators to be very accurate and as literal as possible, in part because they sometimes noted matters where the departure from the original language was very slight. However, at other times some departures may seem surprising, such as when their notes reveal that they left out "spirit" in Gen_7:22. The object of the marginal notes are usually to expand the meaning of a single word or short phrase. In some cases, lengthy phrases or in rarer cases an entire verse is rewritten in the margin. The marginal notes reveal some italics were inconsistent (though perhaps they should be considered vindicated by the content of the marginal notes).

Our methods
We did not include the cross-references from the margins, nor the chapter headings. The notes of the Apocrypha were also not included. To make the notes more user-friendly, we recreated them more-or-less in modern spelling. When an archaic word in the notes was not recognized, the spelling was left "as is."

The text of 1611 used the symbols † and || in the text to indicate the word or the start of a phrase for which there is a marginal note. When a phrase was involved, in a few cases it was difficult to determine the exact length the phrase should be. When doubts surfaced, I used a Hebrew-English or Greek-English interlinear in an attempt to determine the exact phrase that the notes corresponded to. At times the determination of the length of the phrase was unavoidably subjective. The † symbol was used when the margin displayed a more literal Hebrew meaning. A || symbol was used to express another way in which the underlying Hebrew could be translated. The notes themselves in the Old Testament start with the abreviation Hebr. for Hebrew and "or" to designate alternative translations. On a few ocassions the notes are preceded by "i." or "That is," instead. In some rare cases it was obvious that the † and || symbol should have been moved back a word or two. (i.e., 2Ki_8:29, first marginal note, 2Ch_32:6, etc) "&c." was replaced with the more modern "etc."

After the reference, the relevant portion from the text of the 1611 is listed, followed by the marginal note corresponding to that portion with a colon between them. When a colon was used in the original notes, we used a comma instead to prevent confusion. Sometimes the notes capitalized words in what seemed to us an inconsistent manner, but we have attempted to retain the capitalization of the notes as in the original 1611 edition.